The Introduction to Computer Programming course provides an introduction to the fundamental concepts of computer programming and the solution of problems through algorithm design, including parallel programming techniques. Students will dominate the basic pieces of a program starting with control structures using conditional and iterative instructions with logical expressions, as well as the definition and use of variables and data types. They will develop procedures and functions for common tasks that are repeated or are more complex that require decomposition, including recursive functions. They will use structures data types such as arrays, queues, files and pointers. Also, the students will be exposed to the computer’s structure: input and output, memory and central processing unit. A general vision of the Computer Science field and its effect in society, including ethical implications in computation, is included.
During this semester the students in the Introduction to Computer Programming course will be participating in the EIP project: “Engaging Introductory Programming Laboratory”. In this project, sponsored by the TUES program of the National Science Foundation, students will be able to work on laboratory experiences where they will practice the concepts and skills learned in class and obtain attractive products that will motivate them with the possibilities that Computer Science offers them.
Each of the laboratory experiences will use libraries and programming sections that have been developed by professors and students of the Computer Science program of UPR-Río Piedras. When the laboratory experience is completed, the student will not only reinforce the concepts learned in class, but will also get to know products that he or she will be capable of producing with a bit more knowledge and experience in computing.
In today’s laboratory experience you will learn how we will work in the upcoming meetings, how to access the files that will be used and how to hand in the work. You will also learn to manage the basic elements of Qt, the platform that will allow us to develop and execute projects in C++.
Understand the goals of the laboratory for the CCOM 3033 course.
Get to know the laboratory experiences prepared and the general expectations of the laboratory sessions.
Get to know the programming in pairs strategy.
Get to know the rules of the laboratory sessions and the methods of evaluation.
Practice the use of Git and Bitbucket to download and store the necessary files for each laboratory experience.
Practice how to compile, fix errors and execute a programming using Qt.
The criteria to obtain a bonus of 5 points in each laboratory experience are as follows:
During the entire semester the laboratory experiences will be worked on using the programming in pairs technique. In each session the students will be divided in pairs to work on the laboratory experience. Each pair will use one computer and each student in the pair will have one of two roles: conductor and navigator. The conductor will be in charge of writing and editing the code or the requirement for the laboratory. The navigator will read and evaluate what the conductor is writing to indicate if there was an error or to make suggestions. The pairs for each laboratory session will be announced in the Moodle page.
Each laboratory experience contains a section called Pre-Lab. In this section you will find the objectives for the experience and the concepts you should review and study before arriving at the laboratory. There will be a link on the Moodle page for a short quiz that you should take before arriving at the laboratory. The concepts that you should review for the laboratory experience are concepts covered during the course conference sections. The short quiz will also have reading comprehension questions for the laboratory instructions.
The Post-Test is a short test about the same skills and concepts that are evaluated in the Pre-Lab. This test is taken after the laboratory experience concludes. These tests allow us to evaluate the efficacy of the laboratory experience in the learning of concepts and skills through the course. The points obtained will be used as a bonus for the laboratory grade.
When each laboratory experience is over, each pair should hand in the files with the implemented code or some other material. These deliveries will be done using Moodle and the instructions will be included in each laboratory experience.
The instructions for the laboratory experience for this semester are contained in the electronic book you can access in http://ccom.uprrp.edu/~rarce/eipgb/index.html .
In the Moodle page we will indicate the name of the corresponding laboratory for each week and you can access the instructions using the index for the electronic book.
This is a preliminary version of the book and therefore may contain errors. We would appreciate it if you would tell us if you find any errors or if you have any suggestion that could help clarify the instructions.
Bitbucket es is repository or deposit for digital files which can be accessed online and allows the development of group projects in a ordered and simple fashion. The fles for the Introduction to Programming Laboratory will be stored in this site and can be downloaded to your personal computers using Git.
Git is an open source program used to manage program files developed in groups. You can obtain this program in http://git-scm.com/. At the start of each laboratory experience you will download the necessary files to one of the classroom laptops using the command git clone url
from the terminal in each computer.
To use Git in OS X we should use command lines in the terminal. The commands we will use are commands for the Unix operating system. Unix distinguishes between uppercase and lowercase letters. Some basic Unix commands are:
Command | Action |
---|---|
ls | shows a list of the files in the directory |
mv name1 name2 | moves the contents of name1 to file name2 (changes the name of the file) |
cp name1 name2 | copies the contents of name1 to file name2 |
rm name | deletes file |
mkdir name | creates a directory name within the current directory |
cd .. | moves to the previous directory |
cd ~ | moves to the home directory |
cd name | moves to the name directory (within the current one) |
upper arrow | repeats the previous command |
Figure 1. Basic Unix commands.
Qt is a programming application that is used by developers that use the C++ programming language. This environment works in, and can create versions of, applications for different platforms (desktop, mobile platforms, among others). Qt contains an integrated development environment (IDE), called Qt Creator. Within this environment, graphical interfaces can be created and programmed using the design option contained in Qt. We urge you to install Qt on your personal computer and explore the options this application provides.
Each laptop in the laboratory has a virtual machine installed that contains the necessary Qt application to work with the laboratory experiences and a terminal where you can write the Unix commands to download the files.
You can install this virtual machine in your personal computer from the following link: http://eip.ccom.uprrp.edu/vms/eip-ubuntu-qt.tar.gz .
You should use this machine since it contains the version that allows each of the programs in the laboratory experience to work correctly. If you install another version of Qt, you may run into problems with some of the programs.
Qt is application used by professional developers and has many possibilities and options. In each laboratory experience we will see how to use the basic options that we will need during the semester.
For the laboratory we will mostly use the part for editing programs in C++, but there is also an option to design graphical interfaces. This option was used to incorporate the code that presents the graphical interfaces for the laboratory experiences. Learning to use this option is not part of this course, but you can learn to use it on your own. In https://docs.google.com/file/d/0B_6PcmpWnkFBOXJxVDlUNEVfOFk/edit you can find a presentation, prepared by the student Jonathan Vélez, that shows basic aspects on how to use the option for designing graphical interfaces.
Each C++ project is composed of various types of files. In Qt you will have files of type source, header, and form.
Source files: These files have a .cpp
extension (C plus plus) and contain the C++ code for your program. Among these files you will find main.cpp
; this is the file the preprocessor will look for and is where your program starts. Another source file you will find in projects created with Qt is the mainwindow.cpp
file; this file is created by Qt and contains the code associated with the main window designed with the design option (for example the functions that appear below “Private slots”).
Header files: These files have a .h
extension and contain declarations of the functions that are used in the program. During the pre-processing of each program, the instruction #include<name.h>
includes the contents of the file called “name.h” in the code for the .cpp
file that contains this instruction.
Form files: These files have a .ui
extension (user interface) and contain the forms created with the design option. A file you will find in projects created with Qt is the mainwindow.ui
file; this file is created by Qt and contains the design for the main program window.
In today’s laboratory experience you will practice the use of the some of the programs you will use during the semester.
Use the terminal and the command mkdir
to create a directory Documents/eip
for the laboratory files.
To start a C++ project, press the New Project
button or go to the Qt main menu and in File
select New File or Project
. A window similar to the one in Figure 2 will appear. Select Non-Qt Project
, Plain C++ Project
and press Choose
.
Figure 2. Start C++ project without graphical applications.
Write the name of the project, select the directory where you would like to save it, press Continue
in that window and the following one, and then Done
in the next one.
This process will create a new Qt project with the skeleton for a basic C++ program that only displays “Hello World!”. Before continuing, select Projects
in the vertical menu to the left. A window called Build Settings
should appear. In this window, make sure the Shadow build
checkbox is NOT selected, as shown in Figure 3.
---
![figure3.png](images/figure3.png)
**Figure 3.** Do not select the `Shadow build` option.
---
Return to the window where you can edit the program selecting edit
in the left menu and double clicking Sources
and then main.cpp
. Press the green arrow on the left menu to execute the program. The results for the program will be displayed in the terminal window. If there were any errors, these would appear in the Issues
window in Qt.
Change the contents of main.cpp
as such:
#include <iostream>
using namespace std;
int main()
{
cout << endl << "I like the programming laboratory." << endl;
return 0;
}
Press the green button in the left menu to compile and execute the program. A window will appear that offers the option to store the changes. Press Save all
. When executed, if you did not commit any errors, the program will display “I like the programming laboratory.” in the terminal window.
The files for this laboratory experience are stored in Bitbucket. To download these files to your computer go to the terminal window and write the command git clone https://bitbucket.org/eip-uprrp/introduccion.git
.
In this exercise you will practice how to compile, fix errors and execute a program using Qt.
First delete the files created by Qt and close the files from the previous project. To do this, in the Qt main menu go to Build
and select Clean all
; then go to File
and select Close all projects and editors
.
Load the QtCreator
project called Practica
by double clicking the file Practica.pro
in the Documents/eip/introduccion
directory on your computer. In the window that appears, press Configure Project
.
Each time you load or start a new project, make sure that Shadow build
is not selected: in the menu to the left, select Projects
, then in Build Settings
verify that the checkbox for Shadow build
is not selected, as we saw in Figure 3.
As you saw previously, Qt allows you to compile and execute a program by pressing the green arrow that appears in the left column. Press the arrow and notice that you obtain a window of “Issues” that occurred when compiling. The list that appears will show you information that allows you to find and fix the errors.
Select the main.cpp
file in the Sources
directory so you can find and fix the errors.
Fix all of the errors and press the green arrow once again to compile and execute the program. Once you fix the errors, the program should open a window Application Output
and display Exit: 1
.
Build
option of the Qt menu, select Clean All
.During each laboratory experience, each pair will hand in some of the results of their work. These deliveries will be done in the “Deliverables” section that appears in Moodle. Today each student will practice handing in their work individually.
main.cpp
file. Remember to use good programming techniques, including the name of the programmers as a comment at the beginning of the program.